• The Bulletin of The Korean Astronomical Society
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• v.25 no.2
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• pp.34-34
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• 2000

• The Bulletin of The Korean Astronomical Society
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• v.31 no.1
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• pp.26.1-26.1
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• 2006

• The Bulletin of The Korean Astronomical Society
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• v.20
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• pp.16-16
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• 1995

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1062-1073
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• 2007

Acoustic Target Strength (TS) is a major parameter of the active sonar equation, which indicates the ratio of the radiated intensity from the source to the re-radiated intensity by a target. In developing a TS equation, it is assumed that the radiated pressure is known and the re-radiated intensity is unknown. This research provides a TS equation for polygonal plates, which is applicable to near field acoustics. In this research, Helmholtz-Kirchhoff formula is used as the primary equation for solving the re-radiated pressure field; the primary equation contains a surface (double) integral representation. The double integral representation can be reduced to a closed form, which involves only a line (single) integral representation of the boundary of the surface area by applying Stoke's theorem. Use of such line integral representations can reduce the cost of numerical calculation. Also Kirchhoff approximation is used to solve the surface values such as pressure and particle velocity. Finally, a generalized definition of Sonar Cross Section (SCS) that is applicable to near field is suggested. The TS equation for polygonal plates in near field is developed using the three prescribed statements; the redection to line integral representation, Kirchhoff approximation and a generalized definition of SCS. The equation developed in this research is applicable to near field, and therefore, no approximations are allowed except the Kirchhoff approximation. However, examinations with various types of models for reliability show that the equation has good performance in its applications. To analyze a general shape of model, a submarine type model was selected and successfully analyzed.

• YAKHAK HOEJI
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• v.57 no.1
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• pp.63-69
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• 2013

The objectives of the study are to investigate pharmacy remuneration levels stratified by the number of prescriptions dispensing and the type of nearby medical facilities using the Korean National Health Insurance (NHI) database, and to classify community pharmacies based on the characteristics. Claims data of all community pharmacies were extracted from the Korean NHI database from January 1 to June 30, 2010. A total of 14,985 pharmacies were included for the analysis. The remuneration amounts per pharmacist were directly associated with the number of prescription dispensing, and varied by the type of nearby medical facilities where more than 90% of prescriptions dispensed at the pharmacy are issued from. We classified pharmacies to six groups according to the number of prescription dispensing and the type of nearby medical facilities; (1) pharmacies with equal to or less than 200 prescriptions per month per pharmacist, (2) pharmacies near a general hospital, (3) pharmacies near a regular hospital, (4) pharmacies near a clinic, (5) pharmacies near multi clinics, and (6) pharmacies that do not belong to the above types. Compared to pharmacies near a clinic or multi clinics, pharmacies near a general hospital showed a lower number of prescription dispensing per pharmacist, but the income from dispensing fees was higher (p<0.05). The new taxonomy of community pharmacies can be a useful basis for further policy development in pharmacy remuneration system.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.1
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• pp.37-43
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• 2013

Purpose: The present study was conducted to investigate whether the directions of eye movement in playing computer games for certain period affected the change of near point of convergence (NPC) and fusional reserve (FR) or not. Methods: Total 40 subjects in 20s who have the visual acuity of 1.0 or higher without any ocular disease and accommodative dysfunction were asked to successively play computer games. After the subjects were moving eyes in horizontal and vertical directions for 40 and 90 minutes, their horizontal fusional reserves, vertical fusional vergence and near point of convergence were measured. Results: The near point of convergence showed a tendency to be receded after computer gaming in the horizontal and vertical directions, and both of horizontal and vertical fusional reserves were significantly reduced. The range of declined fusional reserves and receded near point of convergence after computer gaming for 90 minutes was smaller than those after computer gaming for 40 minutes. The change of binocular vision was affected by the horizontal eye movement rather than the vertical movement when analyzed by the direction of eye movement. Conclusions: This study revealed that the change in FR and NPC was different along with dominant direction of eye movement during visual display terminal (VDT) tasks. Therefore, the adjustment of VDT working time is required to prevent the dysfunction of binocular vision according to the dominant direction of eye movement during VDT task.

• Journal of Environmental Health Sciences
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• v.43 no.2
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• pp.130-142
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• 2017

Objectives: Although the Korean government is able to implement smoke-free regulations for shared areas in multi-unit housing (MUH), such regulations are limited for private homes. The purpose of this study was to determine the prevalence and predictors of support for the implementation of smoke-free regulations for homes and near the outsides of building among residents in MUH. Methods: A population-based sample of 2,600 residents among a web-based panel in Seoul was included. The residents completed questionnaires including smoking status, voluntary smoke-free home rules, and support for the implementation of smoke-free regulations for homes and near the outsides of building. The presence of a voluntary smoke-free home rule was determined when residents declared that no one smoked inside their homes. Results: Among the 2,600 MUH residents, prevalence of support for the implementation of smoke-free regulations for homes was higher (83.2%) than for near the outsides of buildings (75.1%). Support for the implementation of smoke-free regulations for homes was higher when residents were non-smokers, had voluntary smoke-free home rules, lived with children, lived with more residents, lived in owned homes, lived in apartments, and lived in homes with more frequent secondhand smoke (SHS) incursion. Support for the implementation of smoke-free regulations near the outsides of buildings was higher when residents were women, non-smokers, more educated, had a voluntary smoke-free home rule, lived with children, lived in homes with more frequent SHS incursion, and lived in a commercial area. Conclusions: The majority was supportive of the implementation of smoke-free regulations for homes. Predictors identified in the study can be useful for promoting implementation of smoke-free regulations for homes in MUH.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.302-307
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• 2004

When trains run over a snow-covered track at high speed, the snow accereted under car bodies may drop during train running. The dropped snow/ice lumps scatter the ballast on the track damaging the car body and the environment along the track in snowy regions. In this study, the snow-fall condition in winter around the Seoul-Busan high-speed line has been investigated to yield the countermeasure for the high-speed line. The climate near Japanese and French high-speed line as well as the relationship between the climate and countermeasure has also been investigated and the direction of countermeasure for Seoul-Busan high-speed line has been deduced. Consequently, the amount and frequency of snow-fall near Seoul-Busan high-speed line is less than that of Japan and France, so the speed restriction could be the fundamental countermeasure for Seoul-Busan high-speed line, and additional measure on rolling stock and infrastructure should be followed.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3719-3726
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• 2012

Formation of Z-DNA, a left-handed double helix, from B-DNA, the canonical right-handed double helix, occurs during important biological processes such as gene expression and DNA transcription. Such B-Z transitions can also be induced by high salt concentration in vitro, but the changes in the relative stability of B-DNA and Z-DNA with salt concentration have not been fully explained despite numerous attempts. For example, electrostatic effects alone could not account for salt-induced B-Z transitions in previous studies. In this paper, we propose that the B-Z transition can be explained if counterion entropy is considered along with the electrostatic interactions. This can be achieved by conducting all-atom, explicit-solvent MD simulations followed by MM-PBSA and molecular DFT calculations. Our MD simulations show that counterions tend to bind at specific sites in B-DNA and Z-DNA, and that more ions cluster near Z-DNA than near B-DNA. Moreover, the difference in counterion ordering near B-DNA and Z-DNA is larger at a low salt concentration than at a high concentration. The results imply that the exclusion of counterions by Z-DNA-binding proteins may facilitate Z-DNA formation under physiological conditions.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.5 s.118
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• pp.52-58
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• 2006

Wildlife roadkill is a serious problem for road planners and biologists concerned with traffic safety, species conservation, and animal welfare. The objective of this paper was to analyze the effect of land use on the frequency of mammal roadkills. This study took part in three steps. First, data for 1,279 road kills of nine species were collected by survey over 26 months on 107km of roads near the Mt. Jirisan area. Second, the type of land use near the roadkill points was analyzed, and the area of each land use within loom of the road was calculated using GIS. Finally, the question of whether the land use affects the Sequency of mammal roadkills was analyzed by determining the density of roadkill occurrences for each land-use type. The results of the study were as follows. First, the roadkill density of all species was highest near grasslands, especially natural grasslands. Second, when comparing forests and rice fields, roadkill densities of the Eurasian red squirrel, Siberian chipmunk and Korean hare were higher near the forests, while the densities of the raccoon dog, water deer and leopard cat were higher near rice fields. The results of this study could be an essential information source for mitigating the roadkill problem in Korea.